Motor drive device for air conditioner

Abstract

A motor drive device for an air conditioner has a converter, a three phase inverter and a control means. The converter uses an AC power source as an input source. The three phase inverter receives output voltage from the converter and outputs AC voltage to a motor for the air conditioner. The control means controls the converter so as to maximize efficiency.

1 . A motor drive device for an air conditioner comprising: 
 a converter which receives AC power;    a three phase inverter which receives output voltage from the converter and outputs an AC voltage to a motor for the air conditioner; and    a control means which controls the converter so as to maximize efficiency.    
   
   
       2 . The motor drive device as set forth in  claim 1 , wherein 
 the converter includes a three phase converter.    
   
   
       3 . The motor drive device as set forth in  claim 1 , wherein 
 the converter includes a single phase converter.    
   
   
       4 . The motor drive device as set forth in  claim 1 , further comprising 
 a reactor connected in series to the converter on an input side of the converter; and    a capacitor connected in parallel to the converter on the input side of the converter.    
   
   
       5 . The motor drive device as set forth in  claim 1 , wherein 
 the converter includes pairs of switching devices each connected in series, a number of pairs corresponding to a phase number, and a diode which is connected in parallel to each switching device, the pairs of switching devices are connected in parallel to each other.    
   
   
       6 . The motor drive device as set forth in  claim 1 , wherein 
 the converter includes serial circuits which are connected in parallel to each other, a number of serial circuits corresponding to a phase number, and a diode which is connected in parallel to each switching device in reverse connection, each serial circuit including one switching device and a pair of diodes connected in forward connection and interposing the switching device.    
   
   
       7 . The motor drive device as set forth in  claim 2 , further comprising a reactor connected in series to the converter on an input side of the converter; and a capacitor connected in parallel to the converter on the input side of the converter.  
   
   
       8 . The motor drive device as set forth in  claim 3 , further comprising a reactor connected in series to the converter on an input side of the converter; and a capacitor connected in parallel to the converter on the input side of the converter.  
   
   
       9 . The motor drive device as set forth in  claim 4 , wherein 
 the converter includes pairs of switching devices each connected in series, a number of pairs corresponding to a phase number, and a diode which is connected in parallel to each switching device the pairs of switching devices are connected in parallel to each other.    
   
   
       10 . The motor drive device as set forth in  claim 4 , wherein 
 the converter includes serial circuits which are connected in parallel to each other, a number of serial circuits corresponding to a phase number, and a diode which is connected in parallel to each switching device in reverse connection, each serial circuit including one switching device and a pair of diodes connected in forward connection and interposing the switching device.